Virtual inclination-based adaptive integral robust flow rate control for self-supplied variable-gain servo pumps

Purpose A self-supplied variable-gain servo pump (SVSP) is a useful solution for addressing the inefficient power consumption and rise in the oil temperature of aircraft hydraulic systems. However, owing to the nature of the mathematical model of the pump, the output flow cannot be used to establish a state-space model, making it difficult to apply advanced control strategies and limit the flow regulation performance. The purpose of this study is to achieve high-performance flow regulation of the SVSP by developing advanced control methods. Design/methodology/approach This paper introduces the concept of a virtual inclination angle, which is an equivalent angle representing the effective pump displacement after considering internal leakage and other losses, and transforms flow control into virtual inclination control, developing a disturbance observer-based adaptive integral robust control (DOAIRC) method. Findings Experimental comparisons demonstrate that the proposed method has strong immunity under flow switching and time-varying external disturbances, effectively overcoming the forward channel’s variable gain issue of the SVSP. Practical implications This approach effectively addresses the shortcomings of current flow control methods for servo pumps, which use only traditional control methods or direct equivalents to swashplate inclination control. The DOAIRC method can effectively suppress various dynamic disturbances. This study supports the future development of intelligent airborne hydraulic systems. Originality/value The SVSP’s output flow rate control is innovatively reimagined as regulating the virtual inclination angle, addressing the challenge of using the flow rate as a state variable in the state-space model and accounting for internal leakage. This innovative approach paves the way for a novel adaptive integral robust flow rate control strategy.